The invention relates to radio frequency (RF) devices, and more particularly to low-noise amplifiers (LNA) and radio frequency (RF) receivers having LNAs.
In general, a wide-band RF receiver utilizes a high performance LNA as a front end amplifier. LNAs are characterized by a high signal-to-noise ratio (SNR), excellent linearity across a wide frequency range, and adaptability to a wide range of input signal levels.
To achieve these characteristics, conventional LNAs often include an inductive/capacitive (LC) load. LNAs including a LC load typically exhibit good filtering performance. However, such LNAs also exhibit relatively poor frequency response because the LC load is sensitive to variations in its constituent manufacturing processes. In particular, if a LC load having a higher Q-value is used, LNAs exhibit superior filtering performance but are very sensitive to manufacturing process variations. For this reason, conventional LNAs typically include a LC load having a relatively low Q-value or an expensive LC load carefully calibrated throughout manufacturing. Thus, the choice between conventional LNAs is often a choice between good filtering performance when relatively low Q-value LC load is used, or good frequency response when a relatively high Q-value LC load is used.